This invention relates generally to pneumatic conveyors for conveying particulate matter, and relates more particularly to a receiver for separating conveyed solids from air in a pneumatic conveyor system.
Pneumatic conveyors convey a stream of particulate material fluidized in air through a piping system, and are known to employ a receiver for separating conveyed solids from air at the outlet end of the conveyor. The receiver can take the form of a cyclone separator having a tangential inlet, a bottom outlet for solids, and a top outlet for air. To induce the flow of the conveyed particulates into the receiver through the tangential inlet, a vacuum can be drawn in the receiver through the top outlet. This requires that the bottom outlet be closed. Particulates collected in the receiver must be discharged periodically, however, which requires that the bottom outlet be open. These competing requirements are satisfied with a discharge valve arrangement that can be selectively closed to prevent entry of air whilst drawing a vacuum, and selectively opened periodically to discharge collected particulates. Prior discharge valves have not been entirely satisfactory in meeting both requirements. It would be desirable to provide an improved discharge valve in a receiver of a pneumatic conveyor that more effectively functions as both an air seal and as a discharge flow control valve. This and other desirable attributes are achieved by the present invention.
According to one aspect of the invention, a receiver for a pneumatic conveyor having an improved flow control valve is provided for receiving and discharging particulate matter. The receiver includes an upstanding receptacle having an inlet port and a gravity feed discharge opening. A flow control valve at the discharge opening controls discharge flow of particulate matter from the upstanding receptacle. The flow control valve includes a valve seat circumscribing the discharge opening and a tapered plug selectively engageable with the valve seat to selectively occlude the discharge opening.
It is an object of the present invention to provide a solids/air separating receiver for a pneumatic conveyor having an improved particulate discharge valve.
Other aspects, objects and advantages of the present invention will be apparent from the description below of the preferred embodiment.